From the DE-A-3 710 566, a switch cabinet with an air conditioning device is known, in which the covering wall of the cabinet body and the underside of the air conditioning unit are provided with reciprocally harmonized and aligned and interconnected openings. In this case, an intermediate panel with openings is rigidly connected with the covering wall of the cabinet body. The openings in the intermediate panel are harmonized and aligned with the openings in the covering wall of the cabinet body. The intermediate panel is provided with an upwardly bent rim on three sides. For the detachable connection of the air conditioning unit and the intermediate panel, on the outsides of the oppositely located rims of the interim panel and the outsides facing the same of the air conditioning unit intercalated into the intermediate panel, mutually harmonized locking elements are mounted, each comprising at least one rapid fastening device. The rapid fastening devices used in this case are in the form of manually operable lever locks.
The DE-A-3 532 169 describes a filter for the cooling air of electric equipment provided with a frame-like retaining part insertable from the outside into a wall section of the device as well as with a filter insert, wherein the retaining part possesses connecting elements that are unlockable from the outside for the detachable fixation of the filter in the wall cutout. As connecting element between the filter and the side wall of the device, on the one hand a drag bearing is provided on the underside of the retaining part as well as snap-in clips or brackets on the upper side of the side wall portions. The drag bearing is made up of the rim projecting on the underside and of the retaining projections behind the same via the wall cutout.
On the outside the snap-in clips or brackets each carry a snap-in projection which, in the closing position, engage behind the side wall at the wall cutout. The snap-in clips or brackets are located in a flange continuing in each case in one of the side wall portions, into which, from the front end, marginally open indentations are incorporated for the formation of approximately tongue-shaped snap-in clips and show a forwardly directed extension with a particularly manually operable push button. By means of a reciprocal application of pressure on the push button, the snap-in projections can be disengaged and, subsequently, the filter can be swung out around the drag bearing.
A mounting frame of elastically deformable high polymeric material for the detachable mounting of a substantially rigid accommodation housing containing a measuring instrument in the cutout of a wall with a frame wall disposed vertically to the wall which rests against the wall with fitting shoulders and whose cutout reaches through, while locking tongues of the frame wall project outwardly from the plane of the frame wall and are elastically depressable in the direction of this plane and are provided with sliding surfaces, which enclose an acute angle to the plane of the frame wall and, in the mounting position, engage behind the wall, becomes apparent from the DE-A-2 757 959. A mounting frame serves in this case a coupling element of the measuring device at the wall cutout, which corresponds approximately to the geometric configuration of the punched-out portion in the wall, e.g. of a switch cabinet. The frame wall carries locking tongues which project from the plane of the frame wall and which are elastically depressable in the direction of this plane; in addition, the locking tongues are provided with sliding surfaces. For the connection, the locking tongues engage lockingly in recesses in the wall of the accommodation housing. The attachment in the wall of the switch cabinet is then performed with the aid of further locking tongues. A spring-loaded catch constructed in this manner, in comparison with screwed connections, simplifies an attachment of a measuring instrument or device in a mounting frame because the measuring instrument is merely pressed into the mounting frame and, following this, the entire unit is caused to lockingly engage into the wall of the switch cabinet, however,an adaptation of this spring-loaded catch to differing sheet metal thicknesses of the mounting wall and an alignment and a centering following the effected installation is no longer possible.
In the documents "IBM Technical Disclosure Bulletin, Vol. 32 No. 3k, August 1989, Pages 342-343" and in the DE-U-87 07 975, merely spring-loaded catches for the mounting of axial fans are described.
The RF-shielded installation of a filtering ventilator into the cutout of a mounting panel is known from the DE 195 25 850. The filtering ventilator installed in an RF-shielded manner into the cutout of a mounting panel is comprised of an electrically conducting casing with an accommodation portion for a filter mat, wherein the accommodation portion projects through the mounting panel cutout and has a flange which, with the aid of an electrically conductive adhesive agent, is affixed around the cutout with the mounting panel, wherein, by the interposition of a wire grate, a ventilator is connected to the accommodation portion of the housing projecting from the cutout and the filter mat inserted into the accommodation portion of the housing is covered with the aid of a lamellar grate. In this filtering ventilator, the electrically conducting housing and the electrically conducting grate cover the cutout of the mounting plate in an RF-shielded fashion and the electrically conductive adhesive layer provided between the flange of the housing and the mounting panel seals the point of transition between the housing and the mounting panel in an RF-shielded manner so that an absolutely HF-shielded installation of the filtering ventilator is supposedly ensured. However, the RF-shielded mode of installation of this filtering ventilator does presuppose that the filtering ventilator is comprised of an electrically conducting housing and that, in addition, a wire grate is employed, while, with the aid of an electrically conductive layer of adhesive, the point of transition between the housing and the mounting panel is sealed so as to be RF-shielded. In lieu of an electrically conducting housing it is also possible to employ a housing comprised of a plastic material which is subsequently coated with an electrically conducting layer. A filtering ventilator constructed in this way is not recycelable since all the materials used, viz. plastic, metal, mat and the like cannot be individually separated, for a separation of the housing coated with an electrically conductive coating is possible only to a limited extent and at great expense.
The technical problem of the invention on file is to provide a filtering ventilator and an outlet filter according to the type described in the beginning, which can be mounted so as to be RF-shielded in the cutout of a mounting wall, wherein both the filtering ventilator as well as the outlet filter are recycelable in the form of an environmentally acceptable product in that all the materials used, such as plastic, metal, mat and suchlike, can be individually separated without that e.g. metallic parts call for separate steps from plastic parts connected with or integrated into the latter. Moreover, the filtering ventilator and the outlet filter are to be constructed in such a fashion that, apart from an RF-shielded installation into a mounting wall, also a rigid mounting in the cutouts provided in the mounting walls is possible.